As reported in the annual report for 1991-92, I retired on January 2, 1993. Because of the renovation of the Twinbrook II Facility, I had to vacate my lab space and there was no space available in Building 4 to continue this work. During my retirement, however, I have been able to continue my collaboration with Dr. George Hammer, Department of Chemistry, Georgetown University, the NMR expert on this project. He has identified the two main components to the anti-trypanosomal factor (ATF), a peptide and an alpha-d-glycoside. There is a third component, which remains to be identified. In order to facilitate the work in the elucidation of the chemical structure, I have obtained the collaboration of Dr. Frank Robey, Chief, Peptide and Immunochemistry Unit, Laboratory of Cellular Development and Oncology, NIDR. We are employing reversed- phase high performance chromatography (HPLC) in an attempt to obtain a better separation of the components for the NMR identification. I have been able to perform the trypanosome bioassays (Trypanosoma Equiperdum) in space provided in Building 7 by Dr. Meta Timmons, Chief, Animal Facility, Animal Care Branch, NIAID. An additional, collaborative study is being continued with Dr. Serap Alssoy, MacArthur Center for Molecular Parasitology, Yale University School of Medicine, New Haven, CT. The goal of the study is to clone and express the gene encoding for the AFT-II employing symbionts normally present in the gut of the tsetse fly, the vector of African trypanosomiasis. Re-introduction of such an ATF-producing symbiont into tsetse flies should theoretically prevent trypanosomal infections.